WO2008140168A1

WO2008140168A1 - Method and system for guiding route in turnning point

Info

Publication number: WO2008140168A1
Application number: PCT/KR2007/006617
Authority: WO
Inventors: Ju Han Jung; Kyung Min Lee; Jung Min Kang
Original assignee: Thinkware Systems Corporation
Priority date: 2007-05-16
Filing date: 2007-12-18
Publication date: 2008-11-20

Abstract

The present invention relates to a route guidance method and system in a branch area which provides guidance about a route as an image or voice based on a multiple branch area when multiple on-ramps extending in a same direction and located within a predetermined distance exist on a predetermined route. The route guidance method in a branch area, the route guidance method including: determining whether a moving object moves to a predetermined multiple branch area, the moving object moving according to a predetermined search route; determining a remaining distance to the multiple branch area from the moving object, when the moving object moves to the multiple branch area as a result of the determining; and displaying route guidance information based on the multiple branch area by referring to the determined remaining distance.

Description

METHOD AND SYSTEM FOR GUIDING ROUTE IN TURNNING POINT

Technical Field

The present invention relates to a route guidance method and system using a navigation device, and more particularly, to a route guidance method and system which retrieves and provides guidance about a route to a destination, and enables a user to accurately recognize the route.

Background Art Currently, an apparatus such as a navigation system which retrieves and provides a user with information about a current location and route to a destination desired by a user using a Global Positioning System (GPS), and the like is widely used. Generally, such an apparatus stores map data, receives a satellite signal from a GPS satellite, ascertains a current location of a user on a map stored in the apparatus, and provides a user with services.

A route search service of services provided by such apparatus is most common. When a user sets a destination in a navigation device, the navigation system connects roads in a map stored in the system, and provides a route to a destination. Also, a navigation system may provide guidance about a route to enable a user to accurately recognize a retrieved route. A variety of methods for providing guidance about a route in real time based on a route where a user moves are provided.

Such a route guidance method may be provided using a current location of user and stored map data. However, when a user is located on a complex road or multiple branch areas, the user may not accurately recognize a route. In particular, in a route guidance method in a conventional art, when multiple branch roads in a same direction exist, a user may not exactly recognize which one of the multiple branch roads to enter. Accordingly, a new navigation map matching method and system is required to overcome such a disadvantage.

Disclosure of Invention Technical Goals

The present invention provides a route guidance method and system in a branch area which, when multiple branch areas in a same direction exist, provides accurate guidance about which one of the multiple branch areas is on a route.

The present invention also provides a route guidance method and system in a branch area which provides order voice information according to a route, and thereby may accurately provide a user with a branch area to enter.

The present invention also provides a route guidance method and system in a branch area which enables a user to take a turn in an intersection more accurately and safely.

The present invention also provides a route guidance method and system in a branch area to improve turn guidance information based on information about a surrounding intersection.

Technical solutions

According to an aspect of the present invention, there is provided a route guidance method in a branch area, the route guidance method including: determining whether a moving object moves to a predetermined multiple branch area, the moving object moving according to a predetermined search route; determining a remaining distance to the multiple branch area from the moving object, when the moving object moves to the multiple branch area as a result of the determining; and displaying route guidance information based on the multiple branch area by referring to the determined remaining distance.

According to an aspect of the present invention, the determining whether the moving object moves to the predetermined multiple branch area includes: retrieving map data associated with a location of the moving object moving according to the predetermined search route; and determining whether the moving object moves to the predetermined multiple branch area by referring to the map data.

According to another aspect of the present invention, the determining of the remaining distance includes: determining a current location of the moving object; and determining a remaining distance to each of a plurality of branch areas included in the multiple branch area from the determined current location by referring to the map data.

According to still another aspect of the present invention, the displaying includes: determining whether to display the route guidance information using a remaining distance of each of a plurality of branch areas included in the multiple branch area; and displaying the route guidance information based on the multiple branch area according to a result of the determining.

Brief Description of Drawings

FIG. 1 is a diagram illustrating a route guidance method and system in a branch area according to an embodiment of the present invention;

FIG. 2 is a flowchart illustrating a route guidance method in a branch area according to an embodiment of the present invention; FIG. 3 is a flowchart illustrating an operation of determining whether to display route guidance information according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating an example of displaying route guidance information according to an embodiment of the present invention;

FIG. 5 is a block diagram illustrating a route guidance system in a branch area according to an embodiment of the present invention;

FIG. 6 is a block diagram illustrating a route guidance system in a branch area according to an embodiment of the present invention;

FIG. 7 is a diagram illustrating an example of an intersection including on- ramps adjacent and in a same direction to each other according to an embodiment of the present invention;

FIG. 8 is a flowchart illustrating a route guidance method in a branch area according to an embodiment of the present invention; and

FIG. 9 is a diagram illustrating an example of guidance about a turning point in an intersection, that is, a turn guidance based on adjacent on-ramps in a same direction of a driving direction corresponding to a route according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention

Hereinafter, embodiments of the present invention are described in detail by referring to the figures.

FIG. 1 is a diagram illustrating a route guidance method and system in a branch area according to an embodiment of the present invention. As illustrated in FIG. 1, the route guidance system may provide guidance about a route based on a predetermined search route 102 to a user. When the user enters a current location 101 on the predetermined search route 102, the route guidance system may provide guidance about an access to a branch area in a right direction based on the user.

As illustrated in FIG. 1, another branch area 103 in the right direction may be located close to the branch area on the predetermined search route 102. Accordingly, despite the guidance about the branch area, the user may not determine which one of the predetermined search route 102 and the other branch area 103 is a route to go. That is, when multiple on-ramps in a same direction exist and the multiple on- ramps are located close to each other, the user may have difficulty in recognizing the route using a route guidance method in a conventional art. Accordingly, it is necessary to provide the user with improved route guidance in multiple branch areas illustrated in FIG. 1. FIG. 2 is a flowchart illustrating a route guidance method in a branch area according to an embodiment of the present invention. As illustrated, the route guidance method may be performed in operations S210, S220, and S230.

In operation S210, a route guidance system may determine whether a moving object moves to a predetermined multiple branch area. The moving object moves according to a predetermined search route. Also, the determining in operation S210 may include an operation of retrieving in operation S211 and an operation of moving in operation S212.

In operation S211, the route guidance system may retrieve map data associated with a location of the moving object moving according to the predetermined search route. The map data associated with the location of the moving object may include road information around the moving object.

The map data associated with the moving object may be retrieved in real time since the moving object moves according to the predetermined search route. The map data may be stored in a predetermined storage unit included in the route guidance system or be received from a map data server, and the like. The map data may include the road information around the moving object. The route guidance system may retrieve and identify the road information around the moving object, and the like, in real time depending on a location change of the moving object.

In operation S212, the route guidance system may determine whether the moving object moves to the predetermined multiple branch area by referring to the map data. The multiple branch area may include a plurality of on-ramps in series, and the plurality of on-ramps extends in a same direction.

The multiple branch area may exist on a road, and indicate a predetermined driving area including a plurality of successive branch areas. For example, the multiple branch area may be an area where a plurality of on-ramps in a right direction based on a single main road or road successively exists. Also, the multiple branch area may be an area where a plurality of on-ramps in a left direction successively exists. The route guidance system may determine an area where at least two on-ramps successively exist, other than two successive on-ramps, as the multiple branch area.

The route guidance system may retrieve the map data associated with the moving object in real time, and determine whether the moving object enters the multiple branch area. The route guidance system may store predetermined multiple branch area information for the determination of the multiple branch area, and analyze whether an area corresponds to the multiple branch area through a predetermined determination process in real time. That is, the route guidance system may maintain point data corresponding to the multiple branch area in a predetermined storage unit. Also, the route guidance system may determine whether the multiple branch area exists in the map data associated with a current location of the moving object in real time. A lso, the route guidance system may determine whether the moving object moves to the multiple branch area through a real-time map matching.

When it is determined that the moving object moves to the multiple branch area in operation S212, the route guidance system may perform determining in operation S220. When it is determined that the moving object does not move to the multiple branch area, the route guidance system may perform retrieving in operation S211.

In operation S220, when the moving object moves to the multiple branch area as a result of the determining in operation S212, the route guidance system may determine a remaining distance to the multiple branch area from the moving object. Also, the determining in operation S220 may include an operation of determining in operation S221 and an operation of determining in operation S222. In operation S221, the route guidance system may determine the current location of the moving object. The route guidance system may analyze a Global Positioning System (GPS) signal received from at least four satellites and determine a location of the moving object. In operation S222, the route guidance system may determine a remaining distance to each of a plurality of branch areas included in the multiple branch area from the determined current location by referring to the map data.

The route guidance system may determine the current location of the moving object by referring to surrounding topography information and road information included in the map data, and determine the remaining distance to each of the plurality of branch areas included in the multiple branch area. Specifically, the route guidance system may compare location information of the plurality of branch areas included in the multiple branch area and information of the current location of the moving object to determine the remaining distance. The location information may be coordinate information represented as a predetermined numerical value. The remaining distance may be represented as a mathematical unit in association with a distance. The plurality of branch areas may be a plurality of on-ramps extending in a same direction based on a road or main road where the moving object is driving.

In operation S230, the route guidance system may display route guidance information based on the multiple branch area by referring to the determined remaining distance. The displaying in operation S230 may include an operation of determining in operation S231 and an operation of displaying in operation S232.

In operation S231 , the route guidance system may determine whether to display the route guidance information using the remaining distance of each of the plurality of branch areas included in the multiple branch area. That is, the route guidance information may be determined to be displayed based on the remaining distance of each of the plurality of branch areas, which is described in greater detail with reference to FIG. 3.

In operation S232, the route guidance system may display the route guidance information based on the multiple branch area according to a result of the determining in operation S231. That is, the route guidance system determines whether to display in advance, and then displays the route guidance information as a result of the determining. According to an embodiment of the present invention, however, the route guidance information may be route guidance information when the moving object moves to the multiple branch area. That is, the route guidance system may provide guidance about an existing route based on the determined search route, when the moving object does not move to the multiple branch area, or when it is determined that the route guidance information is not required to be displayed using the remaining distance although the moving object moves to the multiple branch area. Also, the route guidance information may be displayed as an image or voice, which is described in greater detail with reference to FIG. 4. FIG. 3 is a flowchart illustrating an operation of determining whether to display route guidance information according to an embodiment of the present invention. As illustrated in FIG. 3, the determining in operation S231 may include an operation of determining in operation S310 and determining in operation S 320.

In operation S310, the remaining distances of each of the plurality of branch areas included in the multiple branch area may be compared and a comparison remaining distance may be determined. As illustrated in FIG. 3, the determining in operation S310 may include an operation of determining the longest remaining distance in operation S311, an operation of determining the shortest remaining distance in operation S312, and an operation of comparing remaining distance in operation S313. In operation S311, the route guidance system may determine a longest remaining distance from among the remaining distances of the plurality of branch areas.

The plurality of branch areas may be two or more successive branch areas.

The remaining distance of each of the plurality of branch areas is compared and a branch area with a greatest remaining distance value may be selected from the plurality of branch areas. The branch area with the longest remaining distance may be located farthest away from the current location of the moving object. The route guidance system may extract the longest remaining distance value.

In operation S312, the route guidance system may determine a shortest remaining distance from among the remaining distances of the plurality of branch areas. The plurality of branch areas may be two or at least two successive branch areas. The remaining distance of each of the plurality of branch areas is compared and a branch area with a least remaining distance value may be selected from the plurality of branch areas. The branch area with the shortest remaining distance may be located closest to the current location of the moving object. The route guidance system may extract the shortest remaining distance value.

In operation S313, the route guidance system may determine the comparison remaining distance by deducting the shortest remaining distance from the longest remaining distance. The determined longest remaining distance may be greater than the determined shortest remaining distance. When deducting the shortest remaining distance from the longest remaining distance, a distance of the multiple branch area may be determined. The distance of the multiple branch area may be the comparison remaining distance. The comparison remaining distance may increase, as a distance between each branch area increases and as a number of branch areas increases.

In operation S320, when the comparison remaining distance is less than a predetermined reference distance, the route guidance system may determine to display the route guidance information. Also, the reference distance may be determined based on the number of branch areas, and compared to the comparison remaining distance.

When comparing the determined comparison remaining distance and the reference distance, the route guidance information may be determined to be displayed. That is, the determining whether to display the route guidance information may be based on the comparing of the comparison remaining distance and reference distance. The reference distance may be previously determined, stored in the route guidance system, and received from a route guidance server, and the like. The reference distance may be determined depending on the number of branch areas. When the reference distance is not varying regardless of the number of branch areas, a multiple branch area that a user may not recognize may not be accurately determined. The route guidance system may determine whether to display the route guidance information based on the multiple branch area using information about a distance between each of the plurality of branch areas included in the multiple branch area. For example, when three branch areas exist, a distance between a first branch area and second branch area is 500 m, and a distance between the second branch area and third branch area is 2 km, it may be unnecessary to display route guidance information including the third branch area.

FIG. 4 is a diagram illustrating an example of displaying route guidance information according to an embodiment of the present invention.

A route guidance system may divide an enlarged map of a plurality of branch areas by a search route by referring to map data and display the enlarged map of the plurality of branch areas as the route guidance information. The route guidance system may sort order voice information of the plurality of branch areas by the search route by referring to the map data and display the order voice information as the route guidance information. The order voice information may be determined in an ascending order from a branch area with a small remaining distance.

As illustrated in FIG. 4, when the route guidance information is determined to be displayed, the route guidance system may display the route guidance information as an image or voice. Referring to FIG. 4, a moving object moves to two successive branch areas, and thus the route guidance system may determine that the two successive branch areas correspond to a multiple branch area by referring to map data, as described above. Also, the route guidance system may determine a comparison remaining distance through a remaining distance of each of the plurality of branch areas included in the multiple branch area, and determine to display the route guidance information based on the multiple branch area through comparing of the comparison remaining distance and reference distance.

As illustrated in FIG. 4, when a first branch area included in the plurality of branch areas is a search route, the route guidance system may divide an enlarged map 401 of the plurality of branch areas by the search route by referring to the map data and display the enlarged map 401 of the plurality of branch areas as the route guidance information. Accordingly, a user of the route guidance system may recognize a driving direction according to the search route by separately displaying the enlarged map 401 based on the search route. Also, when the first branch area included in the plurality of branch areas is the search route, the route guidance system may sort order voice information of the plurality of branch areas by the search route by referring to the map data and display the order voice information as the route guidance information. The order voice information may be determined in an ascending order from a branch area with a small remaining distance. For example, when two branch areas exist as illustrated in FIG. 4, the route guidance system may display order voice information 402.

Also, as illustrated in FIG. 4, when a second branch area included in the plurality of branch areas is a search route, the route guidance system may divide an enlarged map 403 of the plurality of branch areas by the search route by referring to the map data and display the enlarged map 403 of the plurality of branch areas as the route guidance information. Accordingly, the user of the route guidance system may recognize a driving direction according to the search route by separately displaying the enlarged map 403 based on the search route. Also, when the second branch area included in the plurality of branch areas is the search route, the route guidance system may sort order voice information of the plurality of branch areas by the search route by referring to the map data and display the order voice information as the route guidance information. The order voice information may be determined in an ascending order from a branch area with a small remaining distance. For example, when two branch areas exist as illustrated in FIG. 4, the route guidance system may display order voice information 404.

FIG. 4 illustrates that a case when a user drives according to a predetermined search route. The enlarged map 401 and order voice information 402 when the user drives to a destination of "Seongdong-gu Seongdong #1" according to the search route are illustrated in FIG. 4. Also, the enlarged map 403 and order voice information 404 when the user drives to a destination of "Gangnam-gu Shinsa-dong" according to the search route are illustrated in FIG. 4. The order voice information does not include extra voice guidance such as

"soon", and thus a delay in subsequent voice guidance due to outputting of superfluous voice guidance may be prevented. Also, as described above, the plurality of branch areas may be divided into a first, second, and third branch area.

FIG. 5 is a block diagram illustrating a route guidance system 500 in a branch area according to an embodiment of the present invention.

As illustrated in FIG. 5, the route guidance system 500 may include a multiple branch area determination unit 510, remaining distance determination unit 520, and route guidance display unit 530.

The multiple branch area determination unit 510 may determine whether a moving object moves to a predetermined multiple branch area. The moving object moves according to a predetermined search route. The multiple branch area determination unit 510 may include a map data retrieval unit 511 and determination unit 512.

The map data retrieval unit 511 may retrieve map data associated with a location of the moving object moving according to the predetermined search route. The determination unit 512 may determine whether the moving object moves to the predetermined multiple branch area by referring to the map data. The multiple branch area may include a plurality of on-ramps in series, and the plurality of on-ramps extends in a same direction. The map data associated with the location of the moving object may include road information around the moving object.

The remaining distance determination unit 520 may determine a remaining distance to the multiple branch area from the moving object, when the moving object moves to the multiple branch area as a result of the determining. The remaining distance determination unit 520 may include a current location determination unit 521 and determination unit 522.

The current location determination unit 521 may determine a current location of the moving object. The determination unit 522 may determine a remaining distance to each of a plurality of branch areas included in the multiple branch area from the determined current location by referring to the map data.

The route guidance display unit 530 may display route guidance information based on the multiple branch area by referring to the determined remaining distance. The route guidance display unit 530 may include a display determination unit 531 and display unit 532.

The display determination unit 531 may determine whether to display the route guidance information using the remaining distance of each of the plurality of branch areas included in the multiple branch area. The display determination unit 531 may include a comparison remaining distance determination unit and display determination unit, which are not illustrated. The comparison remaining distance determination unit compares the remaining distance of each of the plurality of branch areas included in the multiple branch area and determines a comparison remaining distance. The display determination unit determines to display the route guidance information when the comparison remaining distance is less than a predetermined reference distance.

The comparison remaining distance determination unit may include a longest distance determination unit, shortest distance determination unit, and determination unit which are not illustrated. The longest distance determination unit determines a longest remaining distance from among the remaining distances of the plurality of branch areas. The shortest distance determination unit determines a shortest remaining distance from among the remaining distances of the plurality of branch areas. The determination unit determines the comparison remaining distance by deducting the shortest remaining distance from the longest remaining distance. The reference distance is determined based on a number of the plurality of branch areas and compared to the comparison remaining distance.

The display unit 532 may display the route guidance information based on the multiple branch area according to a result of the determining. The display unit 532 may divide an enlarged map of the plurality of branch areas by the search route by referring to the map data and display the enlarged map of the plurality of branch areas as the route guidance information, or sort order voice information of the plurality of branch areas by the search route by referring to the map data and display the order voice information as the route guidance information. The order voice information is determined in an ascending order from a branch area with a small remaining distance.

FIG. 6 is a block diagram illustrating a route guidance system in a branch area according to an embodiment of the present invention. FIG. 7 is a diagram illustrating an example of an intersection including on-ramps adjacent and in a same direction to each other according to an embodiment of the present invention. Hereinafter, the route guidance system in the branch area is described with reference to FIGS. 6 and 7.

According to an embodiment of the present invention, the route guidance system includes a GPS module 601 receiving a location signal from at least three GPS satellites and calculating its location. The route guidance system may be a user terminal providing guidance about a route to a destination set by a user. Also, the route guidance system may provide guidance about a turn in an intersection based on on-ramps adjacent to each other when providing guidance about the intersection on the route. The on-ramps extend in a same direction. As illustrated in FIG. 6, the route guidance system may include a route calculation unit 602, storage unit 603, user interface 604, display unit 605, voice output unit 606, and control unit 607. The storage unit 603 includes a map database. The map database includes map data of a national map and route guidance data associated with the map data. The storage unit 603 stores a control program to control an entire operation of the route guidance system including a route guidance function and turning guidance function with respect to the intersection on the route.

The turn guidance function is to provide guidance about a turning direction in the intersection based on on-ramps adjacent to each other, hereinafter, referred to as an adjacent on-ramp. For the turn guidance function, a database with respect to adjacent on-ramps information, hereinafter, intersection database, is required to be established. It is preferable that information about the adjacent on-ramps is analyzed using information about a branch area and intersection for each intersection of the national map to establish the intersection database. The adjacent on-ramps extend in a same direction and are adjacent to each other.

The intersection database is included in the storage unit 603. Also, the intersection database includes the intersections of the national map, possible turning direction for each intersection, and on-ramps adjacent to each other within a predetermined distance with respect to each turning direction.

The turning direction of the intersection is a driving course for each intersection where the user may drive under traffic regulations. Also, the turning direction includes at least one of left turn, right turn, U-turn, P-turn, and rotary turn. The adjacent on- ramps are examined based on each driving course for each intersection, and inputted in the intersection database.

As illustrated in FIG. 7, an intersection includes five on-ramps A, B, C, D, and E. It is assumed that the on-ramp B and on-ramp C are located close to each other within a predetermined distance, and extend in a same direction based on the on-ramp A and on-ramp E.

The on-ramp B and on-ramp C are designated as an adjacent on-ramp with respect to a turning direction towards the on-ramp B and on-ramp C based on the on- ramp A or a turning direction towards the on-ramp B and on-ramp C based on the on- ramp E. The adjacent on-ramp is inputted in the intersection database.

For example, when providing guidance about a right turn from the on-ramp A to the on-ramp C on the route, the on-ramp B is inputted as an adjacent on-ramp with respect to a corresponding turning direction to account for the on-ramp B extending in the same direction as the on-ramp C.

Accordingly, a possible turning direction for each intersection is defined. Also, an exit point and entry point corresponding to each turning direction, and adjacent on- ramp with respect to each of the turning directions, hereinafter, referred to as an adjacent entry point, are inputted in the intersection database. Hereinafter, the adjacent entry point is used in the same way as the adjacent on-ramp. The exit point indicates an on-ramp corresponding to a start point of the intersection based on the turning direction, and the entry point indicates an on-ramp to enter based on a corresponding turning direction It is preferable that the intersection database provides each intersection and adjacent entry point for each turning direction with an identification (ID) based on information update. An ID table of the intersection database is updated, information about each intersection and adjacent entry point may change.

As shown in Table 1, the intersection database includes the ID for each intersection, exit point and entry point with respect to each of the turning directions, and ID for each adjacent entry point of each of the turning directions. <Table 1>

ID for each intersection

Exit point

Entry point

ID for each adjacent entry point

In this instance, at least one adjacent on-ramp may exist, and include a plurality of adjacent entry points. The route guidance system may determine whether the adjacent entry point with respect to the corresponding turning direction exists using the ID for each intersection, exit point and entry point stored in the intersection database. When the adjacent entry point with respect to the corresponding turning direction exists, the route guidance system may provide guidance about a turn in the intersection based on the adjacent entry point.

The route calculation unit 602 ascertains a current location of a user using a GPS signal received through the GPS module 601, and then retrieves a route from the current location to a destination set by a user from map data, stored in the map database of the storage unit 603, and generates route information.

The control unit 607 provides guidance about the route based on the route information generated in the route calculation unit 602. When approaching the intersection on the route, the control unit 607 provides guidance about the turn in the intersection based on an adjacent on-ramp using information stored in the intersection database of the storage unit 603.

Also, the display unit 605 displays map information for the route guidance and a variety of contents according to each system operation. A Liquid Crystal Display

(LCD) or Electro Luminescence (EL) may be used as the display unit 605. The user interface 604 is for inputting a user command with respect to a route guidance function, for example, inputting a destination. The user interface 604 may be a touch pad formed integrally with the display unit 605, and provides a user graphic interface unit. Every menu environment associated with the route guidance function of the route guidance system may be provided as a graphic screen through the display unit 605. A user command may be inputted by touching a particular location on the graphic screen using a stylus pen, fingers, and the like.

The voice output unit 606 provides voice guidance about the route. Specifically, the voice output unit 606 provides voice guidance about the route based on the adjacent on-ramp corresponding to a turning direction in the intersection. FIG. 8 is a flowchart illustrating a route guidance method in a branch area according to an embodiment of the present invention. Hereinafter, the route guidance method in the branch area is described in detail with reference to FIGS. 6 through 8.

In operation S801, a user executes a user menu for destination setting, and sets a destination through the user menu. In operation S 802, when a route guidance service with respect to the set destination is requested, a current location of the user is calculated based on a location signal received through a GPS module 601. Also, in operation S802, a route to the destination from the calculated current location is retrieved.

In operation S803, a map screen and voice guidance with respect to the route is provided for route guidance to enable the user to drive according to the retrieved route.

In operation S804, while providing guidance about the route to the destination, an intersection located ahead in a driving direction is retrieved at regular intervals. For the intersection retrieval, it is determined whether a coordinate value of the intersection located a predetermined distance ahead from the current location, that is, a cross point, exists by referring to map data and intersection location information. The map data is stored in the map database. When the intersection located the predetermined distance ahead is sensed in operation S804, a turning direction in the intersection based on the driving direction on the route is recognized in operation S805. Also, in operation S805, an exit point and entry point of the intersection in the turning direction is recognized.

In operation S 806, an adjacent entry point corresponding to the recognized exit point and entry point is read by accessing information about a corresponding intersection through an ID for each intersection. The ID for each intersection is stored in an intersection database of a storage unit 603.

In operation S807, guidance information about the turn in the intersection is generated using the read adjacent entry point and the generated guidance information is outputted. Accordingly, the turn in the intersection may be provided in operation S 807.

When providing guidance about the turn in the intersection, the entry point to enter may be displayed differently from the read adjacent entry point or voice guidance based on the read adjacent entry point may be provided.

For the voice guidance based on the read adjacent entry point, a location order of the entry point based on the current location of the user may be provided by comparing the entry point corresponding to the route and adjacent entry point.

For example, when an on-ramp B and on-ramp C are located close to each other in a right direction based on an on-ramp A, the on-ramp C is designated as an adjacent entry point 904 with respect to a turning direction from the on-ramp A to the on-ramp B, and the on-ramp B is designated as an adjacent entry point 903 with respect to a turning direction from the on-ramp A to the on-ramp C. The adjacent entry points 903 and 904 are inputted in an intersection database.

As illustrated, when it is assumed that a route 901 to a destination includes a route from the on-ramp A to the on-ramp C, a turning direction 902 in the intersection corresponding to the route 901 is determined when the intersection is sensed.

Also, an exit point (the on-ramp A) and entry point (the on-ramp C) corresponding to the turning direction 902 are determined based on intersection information stored in the intersection database. An adjacent entry point corresponding to the turning direction 902 (the on-ramp B) is read from the intersection database.

That is, the adjacent entry point corresponding to the turning direction 902 on the route 901 may be the on-ramp B which is located close to the on-ramp C and extends in a same direction based on a current location. The turning direction 902 from the on-ramp A to the on-ramp C is displayed to enable a user to drive without confusing on-ramps extending in a same direction on the route 901. Also, voice guidance based on the adjacent entry point 903 (the on-ramp B), for example, "turn right at second on-ramp 500 m ahead" is provided.

A location of an on-ramp which is an entry point corresponding to the turning direction and a location of at least one adjacent on-ramps adjacent to the on-ramp are compared, and thus a location order of the entry point to enter may be provided as voice guidance.

Accordingly, accurate turn guidance in an intersection may be provided based on adjacent on-ramps extending in a same direction based on information stored in an intersection database, when an intersection is sensed.

The above-described embodiment of the present invention may be recorded in computer-readable media including program instructions to implement various operations embodied by a computer. The media may also include, alone or in combination with the program instructions, data files, data structures, and the like. The media and program instructions may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable media include magnetic media such as hard disks, floppy disks, and magnetic tape; optical media such as CD ROM disks and DVD; magneto-optical media such as floptical disks; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include both machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations of the above-described embodiments of the present invention. According to an embodiment of the present invention, a route guidance method and system in a branch area provides order voice information according to a route, and thereby may accurately provide a user with a branch area to enter.

Also, according to an embodiment of the present invention, a route guidance method and system in a branch area provides guidance about a turn in an intersection based on an adjacent on-ramp extending in a same direction based on a current location of a user, and thereby may provide an improved and accurate guidance scheme.

Also, according to an embodiment of the present invention, a route guidance method and system in a branch area provides guidance about a turn in an intersection to enable a user to recognize information more easily, and thereby may reduce user's confusion about an entry or turn in an intersection and provide a safer driving environment.

Although a few embodiments of the present invention have been shown and described, the present invention is not limited to the described embodiments. Instead, it would be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A route guidance method in a branch area, the route guidance method comprising: determining whether a moving object moves to a predetermined multiple branch area, the moving object moving according to a predetermined search route; determining a remaining distance to the multiple branch area from the moving object, when the moving object moves to the multiple branch area as a result of the determining; and displaying route guidance information based on the multiple branch area by referring to the determined remaining distance.

2. The route guidance method of claim 1, wherein the determining whether the moving object moves to the predetermined multiple branch area comprises: retrieving map data associated with a location of the moving object moving according to the predetermined search route; and determining whether the moving object moves to the predetermined multiple branch area by referring to the map data.

3. The route guidance method of claim 1, wherein the multiple branch area includes a plurality of on-ramps in series, the plurality of on-ramps extending in a same direction.

4. The route guidance method of claim 2, wherein the map data associated with the location of the moving object includes road information around the moving object.

5. The route guidance method of claim 2, wherein the determining of the remaining distance comprises: determining a current location of the moving object; and determining a remaining distance to each of a plurality of branch areas included in the multiple branch area from the determined current location by referring to the map data.

6. The route guidance method of claim 2, wherein the displaying comprises: determining whether to display the route guidance information using a remaining distance of each of a plurality of branch areas included in the multiple branch area; and displaying the route guidance information based on the multiple branch area according to a result of the determining.

7. The route guidance method of claim 6, wherein the determining whether to display comprises: comparing the remaining distance of each of the plurality of branch areas included in the multiple branch area and determining a comparison remaining distance; and determining to display the route guidance information when the comparison remaining distance is less than a predetermined reference distance.

8. The route guidance method of claim 7, wherein the determining of the comparison remaining distance comprises: determining a longest remaining distance from among the remaining distances of the plurality of branch areas; determining a shortest remaining distance from among the remaining distances of the plurality of branch areas; and determining the comparison remaining distance by deducting the shortest remaining distance from the longest remaining distance.

9. The route guidance method of claim 7, wherein the reference distance is determined based on a number of the plurality of branch areas and compared to the comparison remaining distance.

10. The route guidance method of claim 6, wherein the displaying of the route guidance information comprises: dividing an enlarged map of the plurality of branch areas by the search route by referring to the map data and displaying the enlarged map of the plurality of branch areas as the route guidance information.

11. The route guidance method of claim 6, wherein the displaying of the route guidance information comprises: sorting order voice information of the plurality of branch areas by the search route by referring to the map data and displaying the order voice information as the route guidance information.

12. The route guidance method of claim 11, wherein the order voice information is determined in an ascending order from a branch area with a small remaining distance.

13. A route guidance method in a branch area, the route guidance method comprising: retrieving a route to a destination set by a user and providing guidance about the route; and providing guidance about a turn in an intersection based on on-ramps adjacent to each other when the intersection is sensed on the route, the on-ramps extending in a same turning direction based on the route.

14. The route guidance method of claim 13, wherein the providing guidance about the route comprises: determining an exit point and entry point in the intersection, the exit point and entry point corresponding to a driving direction of the route; determining an adjacent entry point located within a predetermined distance from the determined entry point; generating guidance information using the determined entry point and adjacent entry point; and outputting the generated guidance information and providing guidance about the turn in the determined entry point.

15. The route guidance method of claim 14, further comprising: collecting intersection information of a national map and establishing a database, wherein the guidance information is generated using the intersection information included in the database.

16. The route guidance method of claim 15, wherein the establishing comprises: providing each intersection of the national map with an identification (ID); designating a possible exit point and entry point in each of the intersections; designating an adjacent entry point located within a predetermined distance from the designated entry point and providing an ID for each adjacent entry point; and establishing a database including the ID for each intersection, exit point, entry point, and ID for each adjacent entry point.

17. The route guidance method of claim 16, wherein the entry point and exit point of the intersection is designated based on each possible turning direction and is included in the database, the turning direction being defined for each intersection.

18. The route guidance method of claim 17, wherein the turning direction is a driving course for each intersection where the user may drive under traffic regulations, and includes at least one of left turn, right turn, U-turn, P-turn, and rotary turn.

19. The route guidance method of claim 16, wherein the adjacent entry point is a point located within a predetermined distance from the entry point with respect to a same turning direction, and included in the database.

20. The route guidance method of claim 16, wherein, when the database is updated, the ID for each intersection, exit point, entry point, and ID for each adjacent entry point, included in the database, change.

21. The route guidance method of claim 16, wherein the providing guidance about the turn in the intersection displays the entry point differently from the adjacent entry point to enable the user to drive to an entry point corresponding to the route.

22. The route guidance method of claim 16, wherein the providing guidance about the turn in the intersection provides voice guidance based on an adjacent entry point adjacent to the entry point to enable the user to drive to an entry point corresponding to the route.

23. The route guidance method of claim 22, wherein the voice guidance provides guidance about a location order of the entry point based on a current location of the user by comparing the entry point corresponding to the route and adjacent entry point.

24. The route guidance method of claim 14, wherein the determining of the exit point and entry point recognizes a turning direction on the intersection based on the route, and determines a point corresponding to a start point of the turning direction as the entry point and a point corresponding to an end point of the turning direction as the exit point.

25. A computer-readable recording medium storing a program for implementing the method according to any one of claims 1 through 24.

26. A route guidance system in a branch area, the route guidance system comprising: a multiple branch area determination unit determining whether a moving object moves to a predetermined multiple branch area, the moving object moving according to a predetermined search route; a remaining distance determination unit determining a remaining distance to the multiple branch area from the moving object, when the moving object moves to the multiple branch area as a result of the determining; and a route guidance display unit displaying route guidance information based on the multiple branch area by referring to the determined remaining distance.

27. The route guidance system of claim 26, wherein the multiple branch area determination unit comprises: a map data retrieval unit retrieving map data associated with a location of the moving object moving according to the predetermined search route; and a determination unit determining whether the moving object moves to the predetermined multiple branch area by referring to the map data.

28. The route guidance system of claim 27, wherein the remaining distance determination unit comprises: a current location determination unit determining a current location of the moving object; and a determination unit determining a remaining distance to each of a plurality of branch areas included in the multiple branch area from the determined current location by referring to the map data.

29. The route guidance system of claim 27, wherein the route guidance display unit comprises: a display determination unit determining whether to display the route guidance information using a remaining distance of each of a plurality of branch areas included in the multiple branch area; and a display unit displaying the route guidance information based on the multiple branch area according to a result of the determining.

30. The route guidance system of claim 29, wherein the display determination unit comprises: a comparison remaining distance determination unit comparing the remaining distance of each of the plurality of branch areas included in the multiple branch area and determining a comparison remaining distance; and a display determination unit determining to display the route guidance information when the comparison remaining distance is less than a predetermined reference distance.

31. The route guidance system of claim 30, wherein the comparison remaining determination unit comprises: a longest distance determination unit determining a longest remaining distance from among the remaining distances of the plurality of branch areas; a shortest distance determination unit determining a shortest remaining distance from among the remaining distances of the plurality of branch areas; and a determination unit determining the comparison remaining distance by deducting the shortest remaining distance from the longest remaining distance.

32. A route guidance system in a branch area, the route guidance system comprising: a database including entry information about an on-ramp and adjacent entry information about an adjacent on-ramp close to the on-ramp, the on-ramp being linked to each intersection in a national map; and a control unit determining, when an intersection is sensed in a route designated by a user, an on-ramp in the intersection, retrieving, from the database, adjacent on- ramp close to the determined on-ramp, and providing guidance about a turn in the on- ramp of the intersection based on the adjacent on-ramp.